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In the present study, 52 sediment samples were collected from 14 sites along the area extending from west of Alexandria (El-MAX) to the eastern side of the Rosetta promontory (the terminal of the Nile River with the Mediterranean Sea). The collected samples were analyzed for radioactive contents. 226 Ra, 228 Ra, 40 K and 137 Cs were detected. The distribution of radionuclide activity and mass concentrations of Th and U displayed a specific pattern that reflects the mineralogical formations and beach stability. Radiological hazards were investigated by calculating the following radiological parameters: the radium equivalent, radiation hazard index and annual effective dose. It was observed that the levels of radiological parameter are higher in eastern locations than in western ones. In addition, the western side displayed radiological parameters higher than the recommended world-wide values.

we present a correlative study of the possible contributions for the two components that may be closely associated with the climate, throughout the last 130 years (1880-2008). We compared the correlation analysis and the power spectral density (PSD) of the Rz and aa with that of the continuous records of the GT in order to get a closer look at a possible connection between them. Our results displayed that the correlations between both (aa & GST) and (Rz & GST) are +0.66 and +0.38, respectively when both parameters Rz and aa precedes by 2-3 yrs. The correlation of GST-aa is two times higher than that of GST-Rz. The GST spectrum reflected significant periods at 21.3-yr, 10.7-11.6 yr variations that observed in the considered geomagnetic and sunspot spectra.

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Silicone rubbers are a good choice for shielding materials because of having elastic and attenuating properties as well as cost-effectiveness. Thus, the aim of this study was to prepare ground-breaking silicone rubber samples by adding WO3-nanoparticles and testing the performance of their radiation shielding ability against Cs-137, Co-60, and Am-241 gamma energy. Increasing the concentration of WO3 nanoparticles in silicone rubber (SR) led to decreasing the half-value layer (HVL) and mean free path (MFP) values determined for the samples tested. Furthermore, the values of MFP and HVL upsurged according to the enhancement of the photon energy. It is noteworthy that the prepared silicone rubber (SR) systems with 50 and 60 wt% concentrations of WO3-nanoparticles displayed lower HVL than the Bi2O3-containing silicone rubber (SR) systems. In the same way, studied silicone rubber SR-W60 represented the lowest HVL comprising iron ore containing silicone rubber.